Let * be a binary operation on Q – {-1} defined by a * b = a + b + ab for all, a, b ∈ Q – {-1}. Then, i. Show that ‘ * ’ is both commutative and associative on Q – {-1}. ii. Find the identity element in Q – {-1}. iii. Show that every element of Q – {-1}. Is invertible. Also, find the inverse of an arbitrary element.